Effects of Nitrogen and Phosphorus Additions on Nutrients and N:P Stoichiometry in Dwarf Lilyturf Roots Effect of Water Management and Phosphorus on Agricultural Characters and As Concentration in Polished Rice of Two Rice Cultivars Differing in P-Efficiency under As-stress Conditions Development of EST Markers Specific to Agropyron cristatum Chromosome 6P in Common Wheat Background Effects of N and P additions on net nitrogen mineralization in temperate typical grasslands in Nei Mongol, China